Lithium LifePo4 12v Batteries - Time For An Upgrade?

I don’t have many photos, here’s one from a GoPro on an outrigger boom hence it makes the canoe look a bit squat, going about 80% max speed there. Minn Kota trolling motor with a cut down shaft and 125Ah AGM. Great fun!

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I just filtered “Sold’ prices; £281 with a starting price of £150, looks like they have increased the starting price to £280.
Any idea what they were used for previously, renewable energy, UPS? Manufacturing date?
Looks like you have the Valence BMS, not sure that I would need that with a single battery, just a voltage monitor should be enough and a pair of chainsaw trousers for the first trip in the canoe with an ’unknown’ 138Ah battery between my legs.
If I do get one I think I’ll get the local battery specialist to give it a check over.
Cheers for the pointer, it’s significantly cheaper than the Renogy.
I take it if you have three you are happy with them.
 
These batteries have an internal BMS, i have the USB cable and software to read the BMS,

so the screen shot above shows the data from the battery, . . .

ie, charge discharge cycles, total wh discharged, any alarm etc etc etc.


I've got another one in my battery box . . . . . . . . .




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These batteries have an internal BMS, i have the USB cable and software to read the BMS,

so the screen shot above shows the data from the battery, . . .

ie, charge discharge cycles, total wh discharged, any alarm etc etc etc.


I've got another one in my battery box . . . . . . . . .




.
Where do you source the software and cable?
 
After weeks on the internet I gave up ....... I Made my own cable.

With comparible software....

I've got the cable and software listed for £19.99

For the green v2 versions.
 
-- Whos Got What ---

heres a nice little peek at @Deaks twin Valence V1 (130ah + 130ah) Black Lifpo4 + Victron install.

currently work in progress . . . .


ACB0F870-102F-4FD5-BA71-167FDFE8F22E.jpeg




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shows us your Lifpo4 installs . . . . .
 
After weeks on the internet I gave up ....... I Made my own cable.

With comparible software....

I've got the cable and software listed for £19.99

For the green v2 versions.
Where do you list the cable and software?
I only have Apple products (IOS), is the software compatible, I’m guessing not as I would need a USB port anyway?
Is there another plug in device that can be used an an bluetooth interface?
 
i had a few on ebay,

software is windows based.

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best way then (for you) is just to fit a Victron Smart shunt or BMV712 and use any device to monitor via bluetooth . .


ie voltage, current, watts, SOC etc etc etc.
 
update and testing . . . .

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I've just bagged myself a third Valence U27-12XP Series 12V 138ah Lifepo4




and they have more in stock - get yours here -->



s-l400.jpg
lifepo4 battery Valence U27-12XP Series 12V 130 amp | eBay
1off lifepo4 battery Valence U27-12XP Series 12V 130 amp. Condition is Used. sold as is where is you decide if fit for use, no warranty given or implied, improper use can lead to injury or death, and no returns. Cash on Collection in person only, and you can pick out your own, check out...
rover.ebay.com




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its in to its time to start testing . . .


ID-3 this time . . .

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first up is a full top charge to 100% . . . The trusty Victron 12/20/1 had this done in no time.

next up was to fully discharge the battery via a power meter. . . . and read the ah, then full charge to 100% again.

that way we will have discharged, and recharged value that the battery can achive, , ,

we then compaire this to the as-new value . . . . for this battery its 138ah new.


lets get started . .

first up lets hook it up.

were using these meters to monitor.

BM2,
current shunt,
bmv712
12v round meter
victron conect to inverter,


1598699244197.png


all connected via the bus bars . .


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lets start so . . . . . 12A to start with via a heat gun . .

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all good, . . .

so time to up the power draw . . .

now adding a dehumidifyer . . . now drawing 45A.

1598699466072.png1598699477678.png1598699498944.png



this is what we have on the thermals at 45A draw , . . .

heatgun and inverter . .

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dehumidifyer and battery in background . .

1598699585312.png


.

notice the heat build up over the trip switch isolator !!!!

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hours later we were at 126ah and the battery voltage started to fall of the clif...


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.

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the bm2 results back up the inline meter . . . . 129ah used.

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and a final BMS check . . . . (note the issue with internal BMS showing 99% full when its empty - but doesnt effect us here)

1598699894661.png



so there we go, the discharge test acheived 126 129 ah from a 138ah battery


im very happy with that.





edit:




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start rest voltage @ 13.5V

45A draw cycling for about 3.5hrs.

discharged capacity from full charge down to 11v cut off @ 126ah.

recharged capacity from 11v cut off to 14.6v float/storage (less than 1amp draw) @ 1256ah



91% capacity from new spec (138ah / 126ah * 100 = 91.3)



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next up was the recharge test to see if the numbers add up . . .

back indoors . .

1598699985579.png

power meter showing the flat battery at 11.9v . .


1598700015333.png


time to re charge . .

30A charge from the victron 12/30/1 . . . .

1598700050432.png

which gets HOT at 30A

1598700090937.png


.

20ah into the charge . .

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thge BM2 readout . . .

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....


i shut it down over night . . . . and carried on the next day . . .


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.


the final result . . . .


4x charge sessions . . .

69.6ah
38.9ah
12.5ah
5.4ah


which total 126ah . . . . . so the numbers add up.


126ah discharged (to 11v) and recharged to float.


im very happy with that . . .

so much so in fact I've ordered another one (to make 4 total )





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so if you want to test your batteries capacity, now you know how.


full charge to float - till the battery draws less than an amp.

discharge through a power meter to read ah used. down to flat or 11v

fully recharge again as above.

the discharge and recharge numbers should add up.



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How awesome is Lithium . . . basically you can use 100% of the stored energy . . .


you cant do that with a SLA or AGM lead based battery !!!!!!!!!

next to no volt drop or sag . . .


pulling 45A for hours on end !!!!



i love them.

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edit:

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start rest voltage @ 13.5V

45A draw cycling for about 3.5hrs.

discharged capacity from full charge down to 11v cut off @ 126ah.

recharged capacity from 11v cut off to 14.6v float/storage (less than 1amp draw) @ 1256ah



91% capacity from new spec (138ah / 126ah * 100 = 91.3)



---
 
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Dell did you change the settings on your victron charger to match your Valence U27-12XP? Screenshot_20200902_154633_com.victronenergy.victronconnect.jpg
 
On the victron mppt and chargers I use the default Lifepo4 setting for the Valence battery.

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Screenshot_20200902-160518.jpg
 
Yes. 14.2v or 14.6v will fully charge the lithium as the charged rest voltage is around 13.5v.
 
I’d be more interested in a direct sale, the Ebay sale prices for a “Used” battery with no comebacks seem to have climbed and not what I would regard as a bargain.
They are $550 USD new in the USA delivered, I realise that there will always be a disparity between UK and US prices.
Gotta link?
These batteries are normally over £1500 each... new apparently

And are Normally only sold to large OEMs
UPS AND BUS batteries
 
Gotta link?
These batteries are normally over £1500 each... new apparently

And are Normally only sold to large OEMs
UPS AND BUS batteries
 
Gotch. Those are used second hand ones, in the USA , states.

Thought they were new ...lol.

These batteries normally sell for £400 up . second hand in the uk
 
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